Wits end with boiler noise

[Michaelsf90]

I'm at my wits end with noise coming from the boiler when it isnt running. From underneath it sounds like someone drilling the wall with a hammer drill. A vibrating noise

I've had every radiator and trv changed as the plumber I use thought it could be a faulty trv. I've had ideal to the boiler. Everyone is stuck as to what it could be because it does it when the boilers off. I've switched the boiler off on the wall when it starts and the noise has continued. Now it only does it when the heating is on or has been on. So its when something is cooling down. Water hammer was suggested but it does it when no water is being used elsewhere in the house. And if it was water hammer would a shock arrester help seeing as the noise is coming from the boiler area. Could it be the magnaclean? I've just found out you can bleed it. I've bled the rads but never bled the magnaclean. Any suggestions really would be much appreciated

 

[Madrab]

Is the pump still running? Pretty difficult to suggest without hearing it.

 

[ianmcd]

what pressure does the boiler pressure guage show when it makes the noise ?

 

[Michaelsf90]

Earlier on I turned the boiler off and it continued to make the noise. The noise had already started tho. The boiler pressure I couldn't say. It may be higher due to the heating having been on or it could be 1.5 bar which is what it normally is

 

[Michaelsf90]

If it was water hammer would it not only do it when water is being drawn off elsewhere in the house. A change in pressure? It always does it when the heatings been on and gone off so its like when something is cooling down

 

[Madrab]

When water pressure is medium or higher pressure, when a valve closes quickly that sends a shock wave down the pipework, if the pipework has long unsupported sections the shockwave sets up a sympathetic vibration, that vibration is called water hammer.

It's not normally associated with boilers, more so solenoid valves (DW/WM) and more recently 1/4 turn valves.

If no water is running but the boiler still emits a vibration/rattle noise then I would suggests it's something else and more likely boiler related. Still difficult without hearing it though.

 

[rbranco]

Make a recording and post here

 

[MeldrewsMate]

Did the boiler noise coincide with having the boiler fitted?
BTW it's good form to include details of the boiler and etc with your post - it helps to clear the crystal ball.

When the heating is ON does the end of the radiator with the TRV get the hottest?

Do you have an 'S' plan heating system, that is two (or more) zone valves rather than just one three-port valve?
Perhaps post a photo of the valve arrangement?

For how long does this banging continue AFTER the heating control has been turned OFF?
Does the banging stop immediately if the mains electricity to the heating system is turned off?

My suspicion is that a new boiler has been fitted, and the flow and return pipework has been transposed. That can only be confirmed or discounted by the data you provide...unless a neighbour has a new hammer drill they're trying out.

 

[Michaelsf90]

I've got a video recording of it but it's too big a file. Il get an audio recording of it today. It started making the noise about 12 months after the boiler was fitted. We had radiators changed downstairs as plumber thought it was a faulty trv. The noise stopped for a month or so after then started again. We had radiators changed upstairs. The noise didnt stop then it continued. It's a single zone, diverter valve. The boiler is an ideal logic 30. I'd say it starts between an hour and half and two hours after the heating has gone off. But then in an evening it can do it in between the heating being on and off when its reached temp. I turned it off yesterday and the noise continued. In the past I have turned it off and the noise stopped. I hope that information helps

 

[Michaelsf90]

When I try to upload a recording it says something about the file does not have an allowed extension

 

[sxturbo]

When I try to upload a recording it says something about the file does not have an allowed extension

Upload it to YouTube then post a link

 

[Hugh Jaleak]

Is your water supply shared with a neighbour?

 

[Michaelsf90]

I'm guessing its shared with the whole street. We have a stop tap under the sink and a stop tap on the road outside

 

[Hugh Jaleak]

No, sounds like you have your own supply. Some older properties had a sub main feeding a number of houses, or one pipe from the main splitting to feed 2 houses, that's why I asked.

 

[Michaelsf90]

Sorry I haven't had time to upload a video yet. Il get on it tomorrow and post the link